When No Sentence States It

Step 1: Before You Read

Watch the idea first — 66 seconds. Then read on, and try it yourself in the next step.

Sometimes the main idea is written down for you. Sometimes no sentence says it, and you have to build it out of what the details share.

Today’s story

What a Beaver Does to a River

An article, in five parts. About 230 words.

Step 2: Read the Story

One part at a time. Press Listen, or read it yourself. The tutor reads along with you.

The tutor shows

Teeth like chiselsA beaver’s front teeth never stop growing. They are orange, and they are harder on the front than on the back, so they wear into a chisel shape as the beaver gnaws. A beaver can bring down a willow as thick as your leg in a single night.

Building the damThe beaver does not eat most of the wood. It drags the branches into the stream and pushes them into a wall, packing the gaps with mud and stones until the water can no longer get through. This wall is called a dam.

Which of these two parts states its main idea in a sentence?

The pond appearsBehind the dam, the stream stops running and spreads out. Within a few weeks there is a pond where there was once a narrow channel. The beaver builds its lodge in the middle of it, with the entrance underwater, where no fox can follow.

Who else moves inThe pond is not only for beavers. Frogs lay their eggs in the still water. Herons stand in the shallows and fish. Dragonflies hunt over the surface, and moss grows on the drowned trunks. A stretch of stream that held a handful of species now holds dozens.

And then a meadowOne day the beavers move on, and the dam breaks. The pond drains, and what is left is a flat bed of rich mud where the water stood. Grass takes it first, then flowers, then young trees. The place that was a stream, and then a pond, becomes a meadow.

Step 3: The Whole Story

Finish reading with the tutor, and the whole story appears here with its parts named.

Step 4: My Notebook

Finish the story first. Then write down two things you noticed.

Step 5: What You Learned

Some paragraphs state their main idea. Many do not.
When none does, find what the details share.
Say it in one sentence of your own, then run both tests on it.

For the grown-up

Unstated main ideas are the common case in real books, and the step children miss is that the answer has to be written by them rather than found. The method is the same afterwards: build a sentence, then test it against every sentence in the paragraph.

When a paragraph has no topic sentence, ask what all its sentences have in common, and make your child say it as one whole sentence.